Http Client Lifetime (ARCH5083)

Key go.performance.http-client-lifetime · Severity error · Category performance

Constructing a new http.Client on every request prevents connection-pool reuse and leads to socket exhaustion. Reuse the client as a single shared instance.

Incorrect

func get(url string) (*http.Response, error) {
  client := &http.Client{Timeout: 10 * time.Second}
  return client.Get(url)
}

Correct

var sharedClient = &http.Client{Timeout: 10 * time.Second}

func get(url string) (*http.Response, error) {
  return sharedClient.Get(url)
}

Fix

Create the http.Client once as a shared instance and reuse it.